1. Field of the Invention
The present invention relates to a process for producing a shaped article, and more particularly, to a process for producing an aluminum alloy shaped article that has an advantageous combination of plural excellent properties, such as strength, rigidity, abrasion resistance and surface hardness, and can be used in a wide field, such as structural materials and members for machines, structural materials and members for automobiles, and members for sport goods.
2. Description of the Prior Art
Various improvements have conventionally been made on an aluminum alloy for the purpose of improving its strength, heat resistance, abrasion resistance, rigidity and the like. Of those improved materials, particle- or fiber-reinforced composite materials, powder metallurgical materials produced, for example, by rapid-solidification, mechanical alloying or the like, are the representative examples thereof. However, those materials have the problems that if strength, abrasion resistance, heat resistance and the like are improved, toughness decreases, and if the concentration or volume rate of various alloying elements or reinforcing particles increases, corrosion resistance decreases. Further, aluminum alloy materials having both abrasion resistance and high strength have not yet been developed. For example, a high strength alloy produced by a rapid-solidification method including gas atomizing is developed. However, this alloy is satisfied with strength characteristics, but it has been difficult to further impart to the alloy other properties such as abrasion resistance, in addition to strength characteristics. Further, gradient materials are proposed in which a mixing ratio of various alloys or particles is continuously changed therein, but such materials are still under investigation. Also, in cladding or co-extrusion method, which is a composite technique for a molten metal material, an entire surface of a first material is covered with a second material. Thus, even unnecessary parts are covered, and the characteristics of the first material cannot sufficiently be exhibited. This may be disadvantageous from the standpoint of costs. In addition, a method by welding such as brazing involves increase in the number of steps, making it difficult to shift the method to automation.